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<center><h1>Quick.java</h1></center><p><br>

Below is the syntax highlighted version of <a href = "Quick.java">Quick.java</a>.
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<pre><tt><span class="comment">/******************************************************************************</span>
<span class="comment"> *  Compilation:  javac Quick.java</span>
<span class="comment"> *  Execution:    java Quick &lt; input.txt</span>
<span class="comment"> *  Dependencies: StdOut.java StdIn.java</span>
<span class="comment"> *  Data files:   </span><span class="url">http://algs4.cs.princeton.edu/23quicksort/tiny.txt</span>
<span class="comment"> *                </span><span class="url">http://algs4.cs.princeton.edu/23quicksort/words3.txt</span>
<span class="comment"> *</span>
<span class="comment"> *  Sorts a sequence of strings from standard input using quicksort.</span>
<span class="comment"> *   </span>
<span class="comment"> *  % more tiny.txt</span>
<span class="comment"> *  S O R T E X A M P L E</span>
<span class="comment"> *</span>
<span class="comment"> *  % java Quick &lt; tiny.txt</span>
<span class="comment"> *  A E E L M O P R S T X                 [ one string per line ]</span>
<span class="comment"> *</span>
<span class="comment"> *  % more words3.txt</span>
<span class="comment"> *  bed bug dad yes zoo ... all bad yet</span>
<span class="comment"> *       </span>
<span class="comment"> *  % java Quick &lt; words3.txt</span>
<span class="comment"> *  all bad bed bug dad ... yes yet zoo    [ one string per line ]</span>
<span class="comment"> *</span>
<span class="comment"> *</span>
<span class="comment"> *  Remark: For a type-safe version that uses static generics, see</span>
<span class="comment"> *</span>
<span class="comment"> *    </span><span class="url">http://algs4.cs.princeton.edu/23quicksort/QuickPedantic.java</span>
<span class="comment"> *</span>
<span class="comment"> ******************************************************************************/</span>

<span class="preproc">package</span><span class="normal"> edu</span><span class="symbol">.</span><span class="normal">princeton</span><span class="symbol">.</span><span class="normal">cs</span><span class="symbol">.</span><span class="normal">algs4</span><span class="symbol">;</span>

<span class="comment">/**</span>
<span class="comment"> *  The </span><span class="keyword">&lt;tt&gt;</span><span class="comment">Quick</span><span class="keyword">&lt;/tt&gt;</span><span class="comment"> class provides static methods for sorting an</span>
<span class="comment"> *  array and selecting the ith smallest element in an array using quicksort.</span>
<span class="comment"> *  </span><span class="keyword">&lt;p&gt;</span>
<span class="comment"> *  For additional documentation, see </span><span class="keyword">&lt;a</span><span class="normal"> </span><span class="type">href</span><span class="symbol">=</span><span class="string">"http://algs4.cs.princeton.edu/21elementary"</span><span class="keyword">&gt;</span><span class="comment">Section 2.1</span><span class="keyword">&lt;/a&gt;</span><span class="comment"> of</span>
<span class="comment"> *  </span><span class="keyword">&lt;i&gt;</span><span class="comment">Algorithms, 4th Edition</span><span class="keyword">&lt;/i&gt;</span><span class="comment"> by Robert Sedgewick and Kevin Wayne.</span>
<span class="comment"> *</span>
<span class="comment"> *  </span><span class="type">@author</span><span class="comment"> Robert Sedgewick</span>
<span class="comment"> *  </span><span class="type">@author</span><span class="comment"> Kevin Wayne</span>
<span class="comment"> */</span>
<span class="keyword">public</span><span class="normal"> </span><span class="keyword">class</span><span class="normal"> </span><span class="classname">Quick</span><span class="normal"> </span><span class="cbracket">{</span>

<span class="normal">    </span><span class="comment">// This class should not be instantiated.</span>
<span class="normal">    </span><span class="keyword">private</span><span class="normal"> </span><span class="function">Quick</span><span class="symbol">()</span><span class="normal"> </span><span class="cbracket">{</span><span class="normal"> </span><span class="cbracket">}</span>

<span class="normal">    </span><span class="comment">/**</span>
<span class="comment">     * Rearranges the array in ascending order, using the natural order.</span>
<span class="comment">     * </span><span class="type">@param</span><span class="comment"> a the array to be sorted</span>
<span class="comment">     */</span>
<span class="normal">    </span><span class="keyword">public</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="type">void</span><span class="normal"> </span><span class="function">sort</span><span class="symbol">(</span><span class="normal">Comparable</span><span class="symbol">[]</span><span class="normal"> a</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">        StdRandom</span><span class="symbol">.</span><span class="function">shuffle</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">);</span>
<span class="normal">        </span><span class="function">sort</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> </span><span class="number">0</span><span class="symbol">,</span><span class="normal"> a</span><span class="symbol">.</span><span class="normal">length </span><span class="symbol">-</span><span class="normal"> </span><span class="number">1</span><span class="symbol">);</span>
<span class="normal">        </span><span class="keyword">assert</span><span class="normal"> </span><span class="function">isSorted</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">);</span>
<span class="normal">    </span><span class="cbracket">}</span>

<span class="normal">    </span><span class="comment">// quicksort the subarray from a[lo] to a[hi]</span>
<span class="normal">    </span><span class="keyword">private</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="type">void</span><span class="normal"> </span><span class="function">sort</span><span class="symbol">(</span><span class="normal">Comparable</span><span class="symbol">[]</span><span class="normal"> a</span><span class="symbol">,</span><span class="normal"> </span><span class="type">int</span><span class="normal"> lo</span><span class="symbol">,</span><span class="normal"> </span><span class="type">int</span><span class="normal"> hi</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span><span class="normal"> </span>
<span class="normal">        </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">hi </span><span class="symbol">&lt;=</span><span class="normal"> lo</span><span class="symbol">)</span><span class="normal"> </span><span class="keyword">return</span><span class="symbol">;</span>
<span class="normal">        </span><span class="type">int</span><span class="normal"> j </span><span class="symbol">=</span><span class="normal"> </span><span class="function">partition</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> lo</span><span class="symbol">,</span><span class="normal"> hi</span><span class="symbol">);</span>
<span class="normal">        </span><span class="function">sort</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> lo</span><span class="symbol">,</span><span class="normal"> j</span><span class="symbol">-</span><span class="number">1</span><span class="symbol">);</span>
<span class="normal">        </span><span class="function">sort</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> j</span><span class="symbol">+</span><span class="number">1</span><span class="symbol">,</span><span class="normal"> hi</span><span class="symbol">);</span>
<span class="normal">        </span><span class="keyword">assert</span><span class="normal"> </span><span class="function">isSorted</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> lo</span><span class="symbol">,</span><span class="normal"> hi</span><span class="symbol">);</span>
<span class="normal">    </span><span class="cbracket">}</span>

<span class="normal">    </span><span class="comment">// partition the subarray a[lo..hi] so that a[lo..j-1] &lt;= a[j] &lt;= a[j+1..hi]</span>
<span class="normal">    </span><span class="comment">// and return the index j.</span>
<span class="normal">    </span><span class="keyword">private</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="type">int</span><span class="normal"> </span><span class="function">partition</span><span class="symbol">(</span><span class="normal">Comparable</span><span class="symbol">[]</span><span class="normal"> a</span><span class="symbol">,</span><span class="normal"> </span><span class="type">int</span><span class="normal"> lo</span><span class="symbol">,</span><span class="normal"> </span><span class="type">int</span><span class="normal"> hi</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">        </span><span class="type">int</span><span class="normal"> i </span><span class="symbol">=</span><span class="normal"> lo</span><span class="symbol">;</span>
<span class="normal">        </span><span class="type">int</span><span class="normal"> j </span><span class="symbol">=</span><span class="normal"> hi </span><span class="symbol">+</span><span class="normal"> </span><span class="number">1</span><span class="symbol">;</span>
<span class="normal">        </span><span class="usertype">Comparable</span><span class="normal"> v </span><span class="symbol">=</span><span class="normal"> a</span><span class="symbol">[</span><span class="normal">lo</span><span class="symbol">];</span>
<span class="normal">        </span><span class="keyword">while</span><span class="normal"> </span><span class="symbol">(</span><span class="keyword">true</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span><span class="normal"> </span>

<span class="normal">            </span><span class="comment">// find item on lo to swap</span>
<span class="normal">            </span><span class="keyword">while</span><span class="normal"> </span><span class="symbol">(</span><span class="function">less</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">[++</span><span class="normal">i</span><span class="symbol">],</span><span class="normal"> v</span><span class="symbol">))</span>
<span class="normal">                </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">i </span><span class="symbol">==</span><span class="normal"> hi</span><span class="symbol">)</span><span class="normal"> </span><span class="keyword">break</span><span class="symbol">;</span>

<span class="normal">            </span><span class="comment">// find item on hi to swap</span>
<span class="normal">            </span><span class="keyword">while</span><span class="normal"> </span><span class="symbol">(</span><span class="function">less</span><span class="symbol">(</span><span class="normal">v</span><span class="symbol">,</span><span class="normal"> a</span><span class="symbol">[--</span><span class="normal">j</span><span class="symbol">]))</span>
<span class="normal">                </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">j </span><span class="symbol">==</span><span class="normal"> lo</span><span class="symbol">)</span><span class="normal"> </span><span class="keyword">break</span><span class="symbol">;</span><span class="normal">      </span><span class="comment">// redundant since a[lo] acts as sentinel</span>

<span class="normal">            </span><span class="comment">// check if pointers cross</span>
<span class="normal">            </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">i </span><span class="symbol">&gt;=</span><span class="normal"> j</span><span class="symbol">)</span><span class="normal"> </span><span class="keyword">break</span><span class="symbol">;</span>

<span class="normal">            </span><span class="function">exch</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> i</span><span class="symbol">,</span><span class="normal"> j</span><span class="symbol">);</span>
<span class="normal">        </span><span class="cbracket">}</span>

<span class="normal">        </span><span class="comment">// put partitioning item v at a[j]</span>
<span class="normal">        </span><span class="function">exch</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> lo</span><span class="symbol">,</span><span class="normal"> j</span><span class="symbol">);</span>

<span class="normal">        </span><span class="comment">// now, a[lo .. j-1] &lt;= a[j] &lt;= a[j+1 .. hi]</span>
<span class="normal">        </span><span class="keyword">return</span><span class="normal"> j</span><span class="symbol">;</span>
<span class="normal">    </span><span class="cbracket">}</span>

<span class="normal">    </span><span class="comment">/**</span>
<span class="comment">     * Rearranges the array so that a[k] contains the kth smallest key;</span>
<span class="comment">     * a[0] through a[k-1] are less than (or equal to) a[k]; and</span>
<span class="comment">     * a[k+1] through a[N-1] are greater than (or equal to) a[k].</span>
<span class="comment">     * </span><span class="type">@param</span><span class="comment"> a the array</span>
<span class="comment">     * </span><span class="type">@param</span><span class="comment"> k find the kth smallest</span>
<span class="comment">     */</span>
<span class="normal">    </span><span class="keyword">public</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="usertype">Comparable</span><span class="normal"> </span><span class="function">select</span><span class="symbol">(</span><span class="normal">Comparable</span><span class="symbol">[]</span><span class="normal"> a</span><span class="symbol">,</span><span class="normal"> </span><span class="type">int</span><span class="normal"> k</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">        </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">k </span><span class="symbol">&lt;</span><span class="normal"> </span><span class="number">0</span><span class="normal"> </span><span class="symbol">||</span><span class="normal"> k </span><span class="symbol">&gt;=</span><span class="normal"> a</span><span class="symbol">.</span><span class="normal">length</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">            </span><span class="keyword">throw</span><span class="normal"> </span><span class="keyword">new</span><span class="normal"> </span><span class="function">IndexOutOfBoundsException</span><span class="symbol">(</span><span class="string">"Selected element out of bounds"</span><span class="symbol">);</span>
<span class="normal">        </span><span class="cbracket">}</span>
<span class="normal">        StdRandom</span><span class="symbol">.</span><span class="function">shuffle</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">);</span>
<span class="normal">        </span><span class="type">int</span><span class="normal"> lo </span><span class="symbol">=</span><span class="normal"> </span><span class="number">0</span><span class="symbol">,</span><span class="normal"> hi </span><span class="symbol">=</span><span class="normal"> a</span><span class="symbol">.</span><span class="normal">length </span><span class="symbol">-</span><span class="normal"> </span><span class="number">1</span><span class="symbol">;</span>
<span class="normal">        </span><span class="keyword">while</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">hi </span><span class="symbol">&gt;</span><span class="normal"> lo</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">            </span><span class="type">int</span><span class="normal"> i </span><span class="symbol">=</span><span class="normal"> </span><span class="function">partition</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> lo</span><span class="symbol">,</span><span class="normal"> hi</span><span class="symbol">);</span>
<span class="normal">            </span><span class="keyword">if</span><span class="normal">      </span><span class="symbol">(</span><span class="normal">i </span><span class="symbol">&gt;</span><span class="normal"> k</span><span class="symbol">)</span><span class="normal"> hi </span><span class="symbol">=</span><span class="normal"> i </span><span class="symbol">-</span><span class="normal"> </span><span class="number">1</span><span class="symbol">;</span>
<span class="normal">            </span><span class="keyword">else</span><span class="normal"> </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">i </span><span class="symbol">&lt;</span><span class="normal"> k</span><span class="symbol">)</span><span class="normal"> lo </span><span class="symbol">=</span><span class="normal"> i </span><span class="symbol">+</span><span class="normal"> </span><span class="number">1</span><span class="symbol">;</span>
<span class="normal">            </span><span class="keyword">else</span><span class="normal"> </span><span class="keyword">return</span><span class="normal"> a</span><span class="symbol">[</span><span class="normal">i</span><span class="symbol">];</span>
<span class="normal">        </span><span class="cbracket">}</span>
<span class="normal">        </span><span class="keyword">return</span><span class="normal"> a</span><span class="symbol">[</span><span class="normal">lo</span><span class="symbol">];</span>
<span class="normal">    </span><span class="cbracket">}</span>



<span class="normal">   </span><span class="comment">/***************************************************************************</span>
<span class="comment">    *  Helper sorting functions.</span>
<span class="comment">    ***************************************************************************/</span>
<span class="normal">    </span>
<span class="normal">    </span><span class="comment">// is v &lt; w ?</span>
<span class="normal">    </span><span class="keyword">private</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="type">boolean</span><span class="normal"> </span><span class="function">less</span><span class="symbol">(</span><span class="usertype">Comparable</span><span class="normal"> v</span><span class="symbol">,</span><span class="normal"> </span><span class="usertype">Comparable</span><span class="normal"> w</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">        </span><span class="keyword">return</span><span class="normal"> v</span><span class="symbol">.</span><span class="function">compareTo</span><span class="symbol">(</span><span class="normal">w</span><span class="symbol">)</span><span class="normal"> </span><span class="symbol">&lt;</span><span class="normal"> </span><span class="number">0</span><span class="symbol">;</span>
<span class="normal">    </span><span class="cbracket">}</span>
<span class="normal">        </span>
<span class="normal">    </span><span class="comment">// exchange a[i] and a[j]</span>
<span class="normal">    </span><span class="keyword">private</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="type">void</span><span class="normal"> </span><span class="function">exch</span><span class="symbol">(</span><span class="normal">Object</span><span class="symbol">[]</span><span class="normal"> a</span><span class="symbol">,</span><span class="normal"> </span><span class="type">int</span><span class="normal"> i</span><span class="symbol">,</span><span class="normal"> </span><span class="type">int</span><span class="normal"> j</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">        </span><span class="usertype">Object</span><span class="normal"> swap </span><span class="symbol">=</span><span class="normal"> a</span><span class="symbol">[</span><span class="normal">i</span><span class="symbol">];</span>
<span class="normal">        a</span><span class="symbol">[</span><span class="normal">i</span><span class="symbol">]</span><span class="normal"> </span><span class="symbol">=</span><span class="normal"> a</span><span class="symbol">[</span><span class="normal">j</span><span class="symbol">];</span>
<span class="normal">        a</span><span class="symbol">[</span><span class="normal">j</span><span class="symbol">]</span><span class="normal"> </span><span class="symbol">=</span><span class="normal"> swap</span><span class="symbol">;</span>
<span class="normal">    </span><span class="cbracket">}</span>


<span class="normal">   </span><span class="comment">/***************************************************************************</span>
<span class="comment">    *  Check if array is sorted - useful for debugging.</span>
<span class="comment">    ***************************************************************************/</span>
<span class="normal">    </span><span class="keyword">private</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="type">boolean</span><span class="normal"> </span><span class="function">isSorted</span><span class="symbol">(</span><span class="normal">Comparable</span><span class="symbol">[]</span><span class="normal"> a</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">        </span><span class="keyword">return</span><span class="normal"> </span><span class="function">isSorted</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> </span><span class="number">0</span><span class="symbol">,</span><span class="normal"> a</span><span class="symbol">.</span><span class="normal">length </span><span class="symbol">-</span><span class="normal"> </span><span class="number">1</span><span class="symbol">);</span>
<span class="normal">    </span><span class="cbracket">}</span>

<span class="normal">    </span><span class="keyword">private</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="type">boolean</span><span class="normal"> </span><span class="function">isSorted</span><span class="symbol">(</span><span class="normal">Comparable</span><span class="symbol">[]</span><span class="normal"> a</span><span class="symbol">,</span><span class="normal"> </span><span class="type">int</span><span class="normal"> lo</span><span class="symbol">,</span><span class="normal"> </span><span class="type">int</span><span class="normal"> hi</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">        </span><span class="keyword">for</span><span class="normal"> </span><span class="symbol">(</span><span class="type">int</span><span class="normal"> i </span><span class="symbol">=</span><span class="normal"> lo </span><span class="symbol">+</span><span class="normal"> </span><span class="number">1</span><span class="symbol">;</span><span class="normal"> i </span><span class="symbol">&lt;=</span><span class="normal"> hi</span><span class="symbol">;</span><span class="normal"> i</span><span class="symbol">++)</span>
<span class="normal">            </span><span class="keyword">if</span><span class="normal"> </span><span class="symbol">(</span><span class="function">less</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">[</span><span class="normal">i</span><span class="symbol">],</span><span class="normal"> a</span><span class="symbol">[</span><span class="normal">i</span><span class="symbol">-</span><span class="number">1</span><span class="symbol">]))</span><span class="normal"> </span><span class="keyword">return</span><span class="normal"> </span><span class="keyword">false</span><span class="symbol">;</span>
<span class="normal">        </span><span class="keyword">return</span><span class="normal"> </span><span class="keyword">true</span><span class="symbol">;</span>
<span class="normal">    </span><span class="cbracket">}</span>


<span class="normal">    </span><span class="comment">// print array to standard output</span>
<span class="normal">    </span><span class="keyword">private</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="type">void</span><span class="normal"> </span><span class="function">show</span><span class="symbol">(</span><span class="normal">Comparable</span><span class="symbol">[]</span><span class="normal"> a</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">        </span><span class="keyword">for</span><span class="normal"> </span><span class="symbol">(</span><span class="type">int</span><span class="normal"> i </span><span class="symbol">=</span><span class="normal"> </span><span class="number">0</span><span class="symbol">;</span><span class="normal"> i </span><span class="symbol">&lt;</span><span class="normal"> a</span><span class="symbol">.</span><span class="normal">length</span><span class="symbol">;</span><span class="normal"> i</span><span class="symbol">++)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">            StdOut</span><span class="symbol">.</span><span class="function">println</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">[</span><span class="normal">i</span><span class="symbol">]);</span>
<span class="normal">        </span><span class="cbracket">}</span>
<span class="normal">    </span><span class="cbracket">}</span>

<span class="normal">    </span><span class="comment">/**</span>
<span class="comment">     * Reads in a sequence of strings from standard input; quicksorts them; </span>
<span class="comment">     * and prints them to standard output in ascending order. </span>
<span class="comment">     * Shuffles the array and then prints the strings again to</span>
<span class="comment">     * standard output, but this time, using the select method.</span>
<span class="comment">     */</span>
<span class="normal">    </span><span class="keyword">public</span><span class="normal"> </span><span class="keyword">static</span><span class="normal"> </span><span class="type">void</span><span class="normal"> </span><span class="function">main</span><span class="symbol">(</span><span class="normal">String</span><span class="symbol">[]</span><span class="normal"> args</span><span class="symbol">)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">        String</span><span class="symbol">[]</span><span class="normal"> a </span><span class="symbol">=</span><span class="normal"> StdIn</span><span class="symbol">.</span><span class="function">readAllStrings</span><span class="symbol">();</span>
<span class="normal">        Quick</span><span class="symbol">.</span><span class="function">sort</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">);</span>
<span class="normal">        </span><span class="function">show</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">);</span>

<span class="normal">        </span><span class="comment">// shuffle</span>
<span class="normal">        StdRandom</span><span class="symbol">.</span><span class="function">shuffle</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">);</span>

<span class="normal">        </span><span class="comment">// display results again using select</span>
<span class="normal">        StdOut</span><span class="symbol">.</span><span class="function">println</span><span class="symbol">();</span>
<span class="normal">        </span><span class="keyword">for</span><span class="normal"> </span><span class="symbol">(</span><span class="type">int</span><span class="normal"> i </span><span class="symbol">=</span><span class="normal"> </span><span class="number">0</span><span class="symbol">;</span><span class="normal"> i </span><span class="symbol">&lt;</span><span class="normal"> a</span><span class="symbol">.</span><span class="normal">length</span><span class="symbol">;</span><span class="normal"> i</span><span class="symbol">++)</span><span class="normal"> </span><span class="cbracket">{</span>
<span class="normal">            </span><span class="usertype">String</span><span class="normal"> ith </span><span class="symbol">=</span><span class="normal"> </span><span class="symbol">(</span><span class="normal">String</span><span class="symbol">)</span><span class="normal"> Quick</span><span class="symbol">.</span><span class="function">select</span><span class="symbol">(</span><span class="normal">a</span><span class="symbol">,</span><span class="normal"> i</span><span class="symbol">);</span>
<span class="normal">            StdOut</span><span class="symbol">.</span><span class="function">println</span><span class="symbol">(</span><span class="normal">ith</span><span class="symbol">);</span>
<span class="normal">        </span><span class="cbracket">}</span>
<span class="normal">    </span><span class="cbracket">}</span>

<span class="cbracket">}</span>

<span class="comment">/******************************************************************************</span>
<span class="comment"> *  Copyright 2002-2015, Robert Sedgewick and Kevin Wayne.</span>
<span class="comment"> *</span>
<span class="comment"> *  This file is part of algs4.jar, which accompanies the textbook</span>
<span class="comment"> *</span>
<span class="comment"> *      Algorithms, 4th edition by Robert Sedgewick and Kevin Wayne,</span>
<span class="comment"> *      Addison-Wesley Professional, 2011, ISBN 0-321-57351-X.</span>
<span class="comment"> *      </span><span class="url">http://algs4.cs.princeton.edu</span>
<span class="comment"> *</span>
<span class="comment"> *</span>
<span class="comment"> *  algs4.jar is free software: you can redistribute it and/or modify</span>
<span class="comment"> *  it under the terms of the GNU General Public License as published by</span>
<span class="comment"> *  the Free Software Foundation, either version 3 of the License, or</span>
<span class="comment"> *  (at your option) any later version.</span>
<span class="comment"> *</span>
<span class="comment"> *  algs4.jar is distributed in the hope that it will be useful,</span>
<span class="comment"> *  but WITHOUT ANY WARRANTY; without even the implied warranty of</span>
<span class="comment"> *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the</span>
<span class="comment"> *  GNU General Public License for more details.</span>
<span class="comment"> *</span>
<span class="comment"> *  You should have received a copy of the GNU General Public License</span>
<span class="comment"> *  along with algs4.jar.  If not, see </span><span class="url">http://www.gnu.org/licenses.</span>
<span class="comment"> ******************************************************************************/</span>
</tt></pre>

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